TECH TIP FOR JANUARY, 1995

  IN THE MARCH "TECH TIP", WE REPORTED THAT ON SOME GM VEHICLES USING THE "Y" SERIES OF ENGINE, A SITUATION CAN EXIST WHERE THE ALTERNATOR WILL NOT CHARGE BECAUSE IT IS NOT SPINNING FAST ENOUGH, EVEN THOUGH ITS BELT IS NEW AND TIGHT. THIS IS BECAUSE THE ALTERNATOR IS DRIVEN BY THE WATER PUMP, BUT THE WATER PUMP IS DRIVEN BY EITHER THE AIR PUMP OR THE P/S PUMP RATHER THAN THE CRANK SHAFT PULLEY. IT IS POSSIBLE TO HAVE THE BELT DRIVING THE WATER PUMP, LOOSE &/OR WORN OUT AND IT WILL NOT SQUEAL BUT IT ALSO WILL NOT DRIVE THE ALTERNATOR FAST ENOUGH TO CHARGE. THE NORMAL SYMPTOM IS THAT THE ALTERNATOR WILL BEGIN TO CHARGE IMMEDIATELY AFTER THE START BUT THE RATE WILL SLOWLY FALL UNTIL YOU CAN READ BATTERY VOLTAGE ONLY. BRINGING THE ALTERNATOR TO ME WILL GET YOU TOLD THAT THERE IS NOTHING WRONG WITH IT. IN THE LAST 6 WEEKS, THREE OF OUR CUSTOMERS HAVE EXPERIENCED THIS PROBLEM (MOSTLY ON OLDER CADILLACS) AND HAVE SPENT CONSIDERABLE NON CHARGEABLE TIME BEFORE FINDING THE CAUSE.

  IN AN RECENT AMERICAN PUBLICATION WAS AN ARTICLE BY AN ACCOUNTING FIRM WHO HAD MADE A COST COMPARISON BETWEEN BUYING A NEW CAR AND KEEPING THE OLD ONE. THEY STARTED WITH A THREE YEAR OLD CAR WHICH WAS PAID FOR, AND WHICH HAD REASONABLE MILEAGE (30000 - 50000 MILES) AND COMPARED THE COST OF ALL ASPECTS OF OPERATING IT FOR THREE MORE YEARS VERSUS USING IT AS A TRADE ON A NEW CAR AND MAKING PAYMENTS FOR THREE YEARS PLUS OPERATING COSTS ON THAT NEW CAR.

   THEIR CONCLUSION WAS, THAT IF YOU KEPT THE OLD CAR FOR A FURTHER THREE YEARS AND THEN SOLD IT (OR TRADED IT ON A NEW CAR), YOU WOULD END UP APPROXIMATELY $3800.00 ($100.00 PER MONTH) IN POCKET AT THE END OF THE THREE YEARS. OBVIOUSLY THE VALUES ARE IN US DOLLARS, BUT IN CANADIAN FUNDS, THIS IS $5200 ($145.00 PER MONTH). THERE ARE VARIABLES WHICH CAN CHANGE THE EQUATION, BUT IT WAS INTERESTING CONCLUSION, AND ONE WHICH BODES WELL FOR THE REPAIR INDUSTRY.

TECHNICAL BULLETIN DATED FEBRUARY, 1994 INDICATES THAT THEFOLLOWING VEHICLES:

1994 ESCORT, MUSTANG, THUNDERBIRD 1994 COUGAR, TRACER 1994 AEROSTAR, EXPLORER, RANGERUSE DIFFERENT SPARK PLUGS IN SPECIFIC CYLINDERS.

BACKGROUND: THREE DIFFERENT & UNIQUE STYLES OF PLATINUM ENHANCED SPARK PLUGS ARE PRODUCED FOR THESE VEHICLES WITH ELECTRONIC IGNITION (EI). EACH STYLE IS DISTINGUISHED BY THEIR PART NUMBER SUFFIX LETTERS.

1) THE SUFFIX LETTER "P" INDICATES THAT THE CENTER ELECTRODE ISENHANCED WITH PLATINUM.

2) THE SUFFIX LETTER "PG" INDICATES THAT THE GROUND (SIDE)ELECTRODE HAS BEEN ENHANCED WITH PLATINUM.

3) THE SUFFIX LETTER "PP" INDICATES THAT BOTH ELECTRODES HAVE BEEN ENHANCED WITH PLATINUM.

THE ABOVE LISTED VEHICLES USE A PLUG WITH DIFFERENT SUFFIX FORSPECIFIC CYLINDERS. ie. 1994 1.9L ESCORT/TRACER USE "PG" INCYLINDERS 1 & 3, AND "P" IN CYLINDERS 2 & 4. IT IS THEREFORE IMPERATIVE THAT IF YOU PULL THE PLUGS FOR INSPECTION THAT THEY BE RETURNED TO THE CYLINDER FROM WHICH THEY CAME. IF YOU ARE REPLACING PLUG ALWAYS USE THOSE WITH A "PP" SUFFIX.

"IMPORT SERVICE", OCT./94 REPORTS THAT THE COOLING FAN &/OR THECONDENSER FAN RUNNING CONTINUOUSLY ON 1992-93 HYUNDAI SONATAS MAY BE CAUSED BY A CORRODED IN LINE DIODE (LETTER CODE W),LOCATED IN THE WIRING HARNESS BEHIND THE BATTERY. THE CORRODED DIODE MAY BECOME MORE CONDUCTIVE DURING WET OR HUMID WEATHER, AND LESS CONDUCTIVE WHEN DRY. THIS MAKES FOR HARD DIAGNOSIS BECAUSE THE CORROSION MAY BE DISRUPTED BY VIBRATION OR YOU MOVING THE WIRE DURING DIAGNOSIS. IF THE FAN RUNS ON IT IS SUGGESTED THAT THE FIRST THING YOU DO IS REPLACE THE DIODE WITH (P/N) 91798©33000.